Add automatic platform version detection

Applying patch suggested by @guilhermeblanco for SQLite's auto-inc integer PKs

See symfony/symfony#10238

Add close() method in MasterSlaveConnection.php

Added support for column collation

Fix sqlite autoincrement detection

Refactor, consolidate and extend driver exception conversion

[DBAL-764] Document types / column usage properly

Add SMALLSERIAL type support on PostgreSQL 9.2 platform

[DBAL-752] Fix integer type declaration SQL on SQLite

Fix unique indexes in CREATE TABLE statements on SQL Anywhere

Fix table lock hints on SQL Anywhere

Fix modifying limit/offset for statements with subqueries on SQL Server

[DBAL-789] Fix default values for TEXT/BLOB column type on MySQL